For some, like Michelle Ramirez, the procedure is a good way to gauge whether or not you really want larger breasts before putting up the money for a permanent breast augmentation surgery.

"It's definitely more of a trial run to see how I would like it," she told ET. "How I feel with bigger breast actually."

While the procedure is not as expensive as a permanent solution, it doesn't come cheap.

"The procedure takes about 20 to 25 minutes," plastic surgeon Dr. Norman Rowe told ET. "It involves a single needle stick into the breast and we inject the saline. The cost of the procedure is roughly about $2,500."

The procedure works by injecting an average of 250cc to 300cc of saline into the breasts which is the equivalent to about a half a bottle of bottled water. After 24 hours, the breasts shrink back to their normal size. Dr. Rowe explained that the saline "slowly gets absorbed into the patient's body and then they urinate it out."